This invention relates to an apparatus which is used in the packaging of cheese and cheeselike products in general. In particular the invention relates to an apparatus which will accept a loaf of cheese, of a standard size, cut it into smaller portions and pass the cut portions on to the next step in the process. The apparatus will accept the standard loaves when they are placed randomly on a conveyor and will accept a loaf only when it has been automatically and properly positioned for ingestion into the cutting portion of the apparatus.
The apparatus is particularly designed for use in the packaging of "cheese," "processed cheese" and "cheese food." "Processed cheese" generally refers to cheese which is made by grinding and mixing together by heating and stirring one or more natural cheeses. The cheese may be of the same or different varieties. Various acids, emulsifying agents and other additives may be included.
"Cheese food" generally refers to cheese product which is prepared from the same materials as indicated above but may have optional dairy ingredients added, such as cream, milk, skim milk, whey. The moisture level of "cheese food" is generally higher than that of processed cheese and has less fat contained therein.
The apparatus of the present invention is designed to be applicable to "cheese," "processed cheese" and "cheese food" all of which shall hereinafter be referred to as "Cheese."
Cheese has been particularly difficult for automatic handling equipment to accomodate. Cheese is a very soft and structurally weak material. It is a material which sticks or tends to cling to any surface upon which it is placed. Additionally its strength and adhesionary characteristics vary with its temperature and atmospheric conditions. Loaves of cheese are formed at elevated temperatures; the loaves cool as the loaf continues its path through the packaging apparatus thus varying its properties. The foregoing factors account for the great difficulty which has been encountered in manufacturing operable, and consistently operable, cheese handling equipment. Machinery which has successfully handled apparently similar food products, such as yeast, have not performed satisfactorily when used with cheese.
Methods for the manufacture of stacked slices of cheese are well known in the prior art. U.S. Pat. 3,900,574 to Warwick issued Aug. 19, 1975 discloses an apparatus for continuously producing a plurality of ribbons of cheese and for stacking and cutting the ribbons of cheese to form loaves of individual slices of cheese.
The rectangular loaves of cheese are generally cut so as to produce a plurality of stacks of square cheese slices. The stacks of square slices of cheese are then wrapped and sealed in a wrapping generally made of cellophane.
There have been many problems encountered in taking the loaves of cheese, cutting them into stacks of square slices of cheese and passing them on to a wrapping machine.
The transporting of the loaves of cheese from the point where they are cut to the cutting machine where they are reduced to the square stacks has been difficult and has required that the cheese be placed on the conveyor in a predetermined manner. The cheese at this point in the process is at an elevated temperature which causes the loaves to stick or adhere to the transporting conveyor.
Various types of conveyors have been used for this purpose. Some of the conveyors have been of the belt type in which the bottom of the lower layer of cheese is entirely in contact with the belt. This type of configuration has resulted in maximum adherence of the cheese to the belt resulting in the lower layer of cheese being torn due to its low strength when the loaf is laterally transferred from the belt. Additionally, this has created difficulty in removing the loaf from the conveyor. An attempted solution for this problem has been to use a conveyor comprised of stationary but rotatable rollers. It was hoped that since the rollers presented less surface area from coming into contact with the cheese there would be less adhesion however, the roller conveyor still produced a torn lower layer in the cheese loaf.
Machines which cut loaves of cheese take a loaf at an intake position and pass the loaf through a plurality of spaced cutting wires called a harp. The loaf of cheese is forced through the harp by a ram which generally has grooves in it, spaced to be compatible with the wires in the harp. In operation the wires of the harp become positioned in the grooves as the ram forces the cheese through the harp. As the loaf passes through the harp the cheese is cut into the desired segments and is passed to an exit point. Such cutting machines generally have had one operating mode wherein the machine is simply turned on and an arm pushes a loaf through the harp to the exit point where it is passed on to the wrapping machine. If no loaf is present at the intake position the arm is still actuated. Thus, heretofore it has been necessary to time the conveyer taking the cheese to the intake point so that a loaf of cheese is present at the intake point at the desired time. This has resulted in a requirement that the loaves be properly positioned on the conveyor and that the conveyor itself be properly timed to the cutting machine. This has resulted in a slow process wherein no more than 30 loaves per minute could be passed. Additionally, if a loaf of cheese was not present at the desired point at some point downstream in the process a void would be presented to the wrapping machine which would cause additional problems. Conventional wrapping machines malfunction when they are operating and the cheese which is to be wrapped is not present.
Many attempts have been made to solve the problem heretofore described. The solutions to these problems had been thwarted by still additional obstacles. As will hereinafter be described it is desirable that the conveyor be comprised of rollers which are continuously driven but will still permit a particular block of cheese to remain stationary.
Heretofore in apparatus of this type the cutting machines utilized a horizontal harp. The loaf of cheese would be placed upon an elevator and raised so as to pass the loaf through the harp thereby cutting it. This process has caused cheese fragments to be forced between adjacent cheese layers as the loaf is passed through the harp. It has additionally resulted in increasing the propensity of cheese particles to remain adhering to the wires of the harp thus producing imperfect and flawed cuts when subsequent loaves are passed through it. It has long been known that a solution to these problems would be to pass the loaf of cheese through a vertical harp thus permitting the cheese fragments to drop and not be forced between adjacent cheese layers. Additionally when the grooved ram which forces the cheese through the harp is disengaged the cheese fragments which would otherwise remain lying on the ram are permitted to fall free. This obvious solution to the problem has been stymied due to difficulty in moving loaves of cheese laterally without damaging the loaf or the resultant portions into which the loaf is cut.